


A Visit To The Lab

by DeathPunkin



Category: Undertale (Video Game)
Genre: Check Up, Creeper Alphys, Dad W. D. Gaster, Fangirl at the end, Heart Play, I dont know what else to tag this with, I gave the skeleton a boner, I love this ship, M/M, Pacifist Route, Sans knows his science, aftertale, lab, magical dick, please dont hate me, robot dick, shoulders are seductive, skeleton dicks, soul play, this is an amalgamation
Language: English
Status: Completed
Published: 2015-12-20
Updated: 2015-12-20
Packaged: 2018-05-07 20:48:05
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,141
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5470331
Author URL: https://archiveofourown.org/users/DeathPunkin/pseuds/DeathPunkin
Summary: <blockquote class="userstuff">
              <p>Sans and Mettaton get up to some other activities in Alphys's lab after she asked Sans to check on the robot.</p>
            </blockquote>





	A Visit To The Lab

**Author's Note:**

> Hi, so um.... yeah please enjoy this.

Sans used to pride himself on science. That was his goal and desired achievement in life. He had learned from the very best, his father W. D. Gaster. Not that they were truly related, it's just that both his and Papyrus's parents had been killed by the humans forcing all of the monsters in here. Gaster was the last of the adult skeletons, and he did his best to take care of Sans and Papyrus. The only thing is, Sans ended up doing a lot of taking care of the younger skeleton. Gaster was a scientist through and through, but he did try his best with both of the boys.  
Sans used to want to be just like that. He wanted to be the same as Gaster, and with each thing he built, Gaster had praised him. Sadly, that slowly drained away the attention he could give to his younger brother Papyrus. Sans often got too tired to do much when he returned home, and that lead to Papyrus's belief in Sans being a lazy older brother. So Sans played it up to fill that expectation too.

  
Several years of hard studying later, he had finally won his onto a study crew with Gaster and the other royal scientists. They were trying to build a machine to take them back to a time before this place existed, so that way they could stop the monsters' entrapment. That was around the time frame of when his life went terribly wrong. They had just figured out the radius needed to transport them all comfortably, and one of the scientists was making ponderous progress with the calibration system. Sans had just gotten back in the room from getting a bottle of ketchup to drink, when all of a sudden the alarm started to go off. Gaster pushed him down, and helped to cover him from the blast. They were just close enough to the outside radius to survive, but sadly those two were the only members of the team to do so. All of their work on the project was destroyed, and ten of the best scientists and monsters now existed only as dusty remains on the floor.

  
"We have to get out of here," Gaster had told him, in that same blocky hand language. So Sans had followed him. They soon sealed of the lab, and Gaster kept the key. Soon Sans noticed that Gaster seemed to keep growing weaker and weaker as the lab remained locked to all except for the eldest skeleton. They both discovered resets together, but it didn't matter how far either of them went back. Gaster still continued to crumble. Eventually, the old man disappeared, leaving the Key to the lab in Sans's hoodie pocket.  
Sans soon noticed that even the memory of Gaster was crumbling, until one day he mentioned the old man and Papyrus asked him how his dreams could be so detailed. He never mentioned the guy again, not even while Frisk ran through, but one person knew. For some reason, videos were the only things to remain after these resets. Alphas knew, because she was constantly watching and re-watching the security tapes caught on the cameras throughout the underground.  
Which is why he is in her lab today."Ch-check u-u-up on Mettaton today o-okay?" Alphys says the mixture of a demand and a question before running away. She's probably going to explore more of the surface with Undine today. That probably means an anime story or two. Oh well, that can handle themselves. It's amazing how much more confident Alphys has gotten since they started dating. Still, it's a little bit annoying that she knows he read through all of Mettaton's plans, and knows exactly how to check up on his parts. It's really to bad that he doesn't know where all of her cameras are.

  
Shrugging to himself, Sans walks into the "examination room" where Mettaton is waiting for him. "So you're the one doing this in the place of Alphys? I hope you know that I require," he rinse his eyes quickly up and down the skeleton, "very special kind of touch" The very charming robot that is for some reason still in his ex form.  
Sans pulls a sly grin at him in response, rolling with the robot's vanity. "You'll find that I have the knowledge of how to do just that," Sans replies in an equally seductive voice. Sans pulls over the clip board Alphys had left him for notes. "I need to check your wires," Sans says dully, then he kicks it up a notch for Mettaton. "Can I open your panel hot stuff, or would you like to?" Sans asks Mettaton, ready to get on with the examination.

  
"Why of course you can see darling~" the robot purrs, pressing a button, and removing his chest plate. Sans quickly does the routine check of the wires before he moves on. Sans feels eyes on him as he flips between writing down the systems checks and staring at the inside of Mettaton's chest. "See anything you like darling?" The Robot purrs at Sans's look of concentration.

  
Mettaton had never seen the skeleton look more focused before, but perhaps that was just part of his charm. "Well of course I do," Sans says, grinning at the robot. He turns the dial on his chest up a few notches. He knows it will send waves of electricity through his robotic body, and those will be perceived as pleasure. Sans is not disappointed by the quiet and breathy moans that begin to eliminate from Mettaton.

  
Sans then holds up the chest plate, and carefully presses it back into place. He knows that since Mettaton s a ghost placed in a machine that he can feel it if his chest is played with. So of course Sans hovers a bit more than necessary, causing a quiet noise to escape the robot. "You know, Alphys never makes check ups feel quite this... stimulating," he purrs while catching Sans's hand between his two.

  
Sans grins in response. "I like to be both the medicine and the sugar," Sans says. So what if he can't think of a pun that his audience of one would get, a joke works just as well here.  
Sans does happen to be a little confused when Mettaton laughs at that. Tori is generally the only one to even chuckle at his jokes, so what's with the seductive laughter. "Can I have both now doctor?" Mettaton asks in a seductive way that feigns innocence.

  
"How about after I finish your check up?" He replies equally seductively. Just as Mettaton begins to complain, he feels the container with his soul open from a button press. Sans waits until another pleasurable surge of every is passing to gently finger his soul. His hands get a little gooey, and he notices a small tube at the bottom of the container. Sans briefly wonders why that is there since it wasn't n the plans, but he is interrupted by a loud moan from Mettaton.

  
"Do that again darling~" the robot pleads with him. Sans keeps up the light touches for a bit before really getting in there for a good l, seductive rub down. Mettaton groans and shrieks at the peaks of pleasure from the fleeting rough treatment surrounded by teasingly light touches. After a while he groans, and slideshow waist band of seductive black pants down. "You have me all hard and bothered here darling," he says, gesturing to his dick by teasingly fingering the metallic head.  
"Oh really?" Sans asks, and at a nod, he pulls a strange white thing out of his pants and gives it a few strokes. "I would say that you're doing the same to me," he replies, allowing Mettaton to finally realize that that is his dick, and it just so happens to be a Bonner in every sense of the word. It looks like some kind of bone ending in a rounded tip, almost like the shoulder socket portion would be on a very small child. There also just so happens to be a blue liquid slowly oozing from the tip of it, and no holes that he could find anywhere. "Like what you see?" Sans asks, and Mettaton can't help but nod.

  
Mettaton leans back on the bed in a lounging position. "Come join me," he purrs, beckoning the skeleton over with his super sexy legs.  
Sans comes over solely, and then leans over Mettaton, supporting his weight with his hands and gangly nibbling at the junction between Mettaton's neck and shoulder pads. Mettaton groans at the feeling, and Sans knows that he stimulated the spot enough. Sans is surprised by the reaction he gets when he plays with that spot just a bit more.  
Suddenly Mettaton flips them over, and he seductively grinds down on Sans's erection, causing them both to moan out in pleasure. Sans grabs them both and starts pumping, only to find a pinkish liquid oozing from Mettaton's metal dick. So that's what the hole in the bottom of his soul container was for. "I can't handle it darling, I want to be inside of you," Mettaton pleads. For some reason, Sans agrees.

  
So Mettaton pulls his pants down the rest of the way, and Sans follows suit by taking off his shorts. This is the first chance that Mettaton has had to really explore the other. He touches the dick suspended by Blue magic, and runs his hands downward. He finds a small opening in the magic, and presses a finger teasingly around the edge. Sans shudders, and that leaves Mettaton just enough time to reach up and pop open his soul container.

  
Much to his surprise and pleasure, he finds Sans coating his fingers in the stick liquid pouring from Mettaton's heart. Said robot groans in pleasure, and leans back in a blessed out haze at the treatment. It takes a few moments, but he clears up enough to see the very sexy image of Sans hastily preparing himself. Mettaton plays with himself as he watches, but by the third finger, he can't take it anymore.

  
Mettaton lunges forward and pulls Sans's hand away. The skeleton whimpers a bit at the loss of his fun, but that soon gets replaced by a groan as Mettaton enters him fully. They both settle for a moment, before Mettaton begins a bruising pace. He thrusts swiftly in and out of Sans causing them both to groan at the feeling. Mettaton opens his sexy eyes, and looks down to see how Sans is groaning and oh so very close. He slows his thrusts down until they are agony for the both of them. "Plead for me darling," he coos in as seductive of a whisper as he can manage.

  
Normally Sans would resist, but by now he's too far gone to care. He whimpers for more. Not loudly, just the quiet moaning sound. "S-sorry darling. That. Isn't. Enough," he accentuates each word with a harsh thrust before returning to the teasing lightness of before. Sans gets fed up with the treatment, and instead turns the dial up two more notches. Mettaton purrs at the increased sensation pouring through him. "You sure have a way of begging that I enjoy," is what Sans finally manages to make out from the garbled noise, and breathy moans that come out of Mettaton. The Robot finishes that sentence with paying some much needed attention to Sans's weeping dick. He rubs it harshly in time with his own thrusts into the Skeleton. Sans seems to enjoy the little shocks traveling down his dick, in fact, he seems to like them.

  
It doesn't take much longer for them to both cry out in mutual bliss as they reach their peaks together. They snuggle together before Mettaton finally falls down. His hips sag downward onto Sans's pelvic bone. He stares at the skeleton for a moment with a strange look on his face. "Those only appear when I need them," is his response, and Mettaton just snuggles back into his body. The robotic star slips into sleep mode, and Sans idly reaches up to turn down the dial back to its normal setting before joining the robot in a nap on the exam table.  
.........  
Alphys stares happily at the recorded footage. She's not a very big fan of live action. In fact, unless it involves her and Undine she can hardly stand sexual things in real life at all. Still, she finds this beyond perfect. An unknown scientist, or at least one that wasn't the normal one and the right atmosphere had gotten this rolling perfectly. People on the internet often don't believe that things like this can happen. Still this only makes Alphys wonder how she can further her new ship.

**Author's Note:**

> Okay, so the shoulder joint thing is a multi layered joke. At my school, showing shoulders is now against the dress code. That started upholds of shoulders being inappropriate because there is nothing really said about cleavage. So I also happen to find the end of arm bones to be rather phallic. Since the skeleton brothers attack with bones, I found it appropriate to give him a dick of a half formed magical bone thing. After it is no longer needed, it disappears. The thing with Mettaton can be explained as well. We all know that Alphys is shipping trash,and I thought that would extend to Mettaton. She accidentally showed Asgore a picture of two robots making out when she was explaining anime to him. That proves that she ships robots and stuff, so she probably would give him some sort of genitalia anyway. Hopefully that helps clear up any confusion.


End file.
